Tracing the journey of poxviruses: insights from history

The historical significance of the poxviruses is profound, largely due to the enduring impact left by smallpox virus across many centuries. The elimination of smallpox is a remarkable accomplishment in the history of science and medicine, with centuries of devoted efforts resulting in the development and widespread administration of smallpox vaccines. This review provides insight into the pivotal historical events involving medically significant poxviruses. Understanding the remarkable saga of combatting smallpox is crucial, serving as a guidepost for potential future encounters with poxvirus infections. There is a continual need for vigilant observation of poxvirus evolution and spillover from animals to humans, considering the expansive range of susceptible hosts. The recent occurrence of monkeypox cases in non-endemic countries stands as a stark reminder of the ease with which infections can be disseminated through international travel and trade. This backdrop encourages introspection about our journey and the current status of poxvirus research.

COVID-19 and tuberculosis coinfection: A case-control study from a tertiary care center in South India

Context

Coronavirus disease 2019 (COVID-19) and tuberculosis (TB), are presently the major infectious diseases imposing a consequential public health threat and their coinfection has a significant impact on the outcome.

Aims

To evaluate the clinical features and outcomes of COVID-19-TB coinfected cases compared to solely COVID-19-infected cases.

Settings and Design

A retrospective observational study was conducted between August 1, 2020, to February 28, 2022, at a tertiary care hospital.

Materials and Methods

In this case-control study, an equal number of gender-age-matched COVID-19 and TB coinfected patients and COVID-19 cases without TB were included using simple random sampling.

Statistical Analysis Used

The data was analyzed using SPSS v 26. Categorical variables were compared using the Chi-square test, and an independent t-test or Mann-Whitney U test was applied for the quantitative variables in the univariate analysis. A P-value of less than 0.05 was considered significant.

Results

A total of 27 patients were included in each group. Upper lobe involvement (44%) and pleural effusion (22%) were significantly more common in TB-COVID-19 cases when compared to the control group (7% and 4%, respectively; P < 0.05). Moreover, median levels of C-reactive protein and ferritin were significantly higher in TB-COVID-19 coinfection.

Conclusions

Chest radiology and a higher level of certain biomarkers like C-reactive protein and ferritin can help to suspect TB in COVID-19 patients and vice-versa.

The altered sputum microbiome profile in patients with moderate and severe COPD exacerbations, compared to the healthy group in the Indian population

Background: Microbial culture-independent sequencing techniques have advanced our understanding of host-microbiome interactions in health and disease. The purpose of this study was to explore the dysbiosis of airway microbiota in patients with moderate or severe chronic obstructive pulmonary disease (COPD) and compare them with healthy controls. Methods: The COPD patients were investigated for disease severity based on airflow limitations and divided into moderate (50%≤FEV1<80% predicted) and severe groups (FEV1<50% predicted). Spontaneous sputum samples were collected and, the V3-V4 regions of the 16S rRNA coding gene were sequenced to examine the microbiome profile of COPD and healthy participants. Results: A total of 45 sputum samples were collected from 17 severe COPD, 12 moderate COPD cases, and 16 healthy volunteers. The bacterial alpha diversity (Shannon and Simpson's index) significantly decreased in the moderate and severe COPD groups, compared to healthy samples. A significantly higher proportion of Firmicutes and Actinobacteria were present in moderate COPD, and Proteobacteria numbers were comparatively increased in severe COPD. In healthy samples, Bacteroidetes and Fusobacteria were more abundant in comparison to both the COPD groups. Among the most commonly detected 20 bacterial genera, Streptococcus was predominant among the COPD sputum samples, whereas Prevotella was the top genus in healthy controls. Linear discriminant analysis (LDA>2) revealed that marker genera like Streptococcus and Rothia were abundant in moderate COPD. For severe COPD, the genera Pseudomonasand Leptotrichia were most prevalent, whereas Fusobacterium and Prevotella were dominant in the healthy group. Conclusions: Our findings suggest a significant dysbiosis of the respiratory microbiome in COPD patients. The decreased microbial diversity may influence the host immune response and provide microbiological biomarkers for the diagnosis and monitoring of COPD.

Tuberculosis screening for pediatric household contacts in India: Time to adapt newer strategies under the National TB Elimination Programme!

INTRODUCTION

The study aimed to evaluate the effectiveness of screening pediatric household contacts (under the age of 15 years) for tuberculosis (TB) in India through verbal screening, tuberculin skin testing, and chest radiography at intervals of 0, 3, 6, 9, and 12 months. The study also aimed to determine the proportion of contacts who tested positive for TB and to describe the challenges in implementing regular follow-up. Current National TB Elimination Programme (NTEP) guidelines only require verbal screening for contacts under 6 years old at TB treatment initiation. The study aimed to fill this knowledge gap and provide valuable insights for improving TB screening in pediatric household contacts in India.

METHODS

The study was conducted in two districts of Karnataka, India from 2021 to 2022, and utilized a cohort study design to enroll contacts of index tuberculosis (TB) cases diagnosed under the National TB Elimination Programme (NTEP). Participants were followed up at regular intervals for one year to evaluate the effectiveness of TB screening in pediatric household contacts.

RESULTS

In this study, 686 pediatric household contacts were enrolled and screened for tuberculosis (TB) using verbal symptom screening, tuberculin skin testing (TST), and chest radiography. Projected figures estimated that 0.8%, 42%, and 4% of contacts would test positive for symptomatic screening, TST, and chest radiography, respectively. TB cases were detected in 2.91% (1.84-4.38) of contacts, with females above 6 years of age having a 22% higher risk of contracting the infection than males above 6 to < 15 years. However, not all cases were subjected to TST and chest radiography. The primary reason for not investigating child contact for TB was their reported healthy or asymptomatic status.

CONCLUSION

The implementation of regular screening intervals for tuberculin skin test (TST) and chest radiography, along with verbal screening, among pediatric household contacts under the age of 15 years seems to be beneficial for the National TB Elimination Programme (NTEP), despite the challenges faced during implementation. Innovative strategies should be explored by NTEP to ensure effective implementation.

Risk factors for the development of tuberculosis among the pediatric population: a systematic review and meta-analysis

Pediatric tuberculosis is a major cause of mortality and morbidity in children due to high transmission, poor diagnostic tools, and various respiratory diseases mimicking TB. Identifying risk factors will provide evidence for clinicians to strongly relate their diagnosis to the associated pathology. Studies were retrieved from PubMed, Embase, and Google Scholar, systematically reviewed, and meta-analyzed for various risk factors and their association with pediatric TB. Meta-analysis depicted that four out of eleven risk factors were significant-contact with known TB cases (OR 6.42 [3.85,10.71]), exposure to smoke (OR 2.61 [1.24, 5.51]), overcrowding in the houses (OR 2.29 [1.04, 5.03]), and, poor household conditions (OR 2.65 [1.38, 5.09]). Although significant odds ratio estimates were obtained, we observed heterogeneity in the studies included.    Conclusion: The study findings demand the constant screening of risk factors such as contact with known TB cases, exposure to smoke, overcrowding, and, poor household conditions for the development of pediatric TB. What is Known: • Knowledge of the risk factors of a disease is of utmost importance in the planning and institution of its control measures. Well-established risk factors in the occurrence of TB in the pediatric group are HIV positivity, older age and close contact with a known case of TB. What is New: • In addition to what is already known; this review and meta-analysis has identified exposure to indoor smoking, overcrowding and poor household conditions as important risk factors for developing pediatric TB. • Implications of the study: The findings highlight that in addition to routine contact screening for the pediatric group, the children living in poor household conditions and getting exposed to passive indoor smoking demand more attention to prevent the development of pediatric TB.

A ten-year retrospective analysis of nocardiosis in a tertiary care center of South-coastal India

Nocardiosis is an uncommon life-threatening infection caused by Nocardia spp. This study aimed to review the distribution of risk factors, clinical characteristics, microbiological findings, treatment and outcome of patients diagnosed with nocardiosis. This study was a retrospective case record review of all nocardiosis cases that were diagnosed at our tertiary care hospital from January 2008 to December 2019. A total of 48 patients with a mean age of 52.2±16.28 years were included. Out of which forty one (85%) were diagnosed as pulmonary nocardiosis and seven (14.6%) as disseminated disease. Chronic lung disease 25 (52.1%), long term steroid use 22 (45.8%) followed by diabetes mellitus 11 (22.9%) were common predisposing factors. The common symptoms were fever (87.5%), cough (79.2%) and breathlessness (52.1%). The most frequent radiologic finding included consolidation in 38 (79.1%), cavitation with thickened wall in 2 (4.1%), reticulonodular shadows in 2 (4.1%), and unilateral pleural effusion in 5 (10.4%). Nocardia otitidiscaviarum (22.9%) was frequently isolated from cultures. Resistance to trimethoprim-sulfamethoxazole (TMP-SMX) was observed in 21% cases. Mortality was noted in 6 (12.5%) patients and all were with pulmonary involvement. The percentage of death among those with and without pulmonary tuberculosis was 33.3% and 5% respectively. Patients affected by pulmonary nocardiosis with previous history of pulmonary tuberculosis showed significant association with poor outcome (p-value=0.05). In conclusion, nocardiosis mainly affects patients with structural lung disease or immunocompromised hosts with adverse outcome. Awareness of this infection is crucial for a clinician, and any suspicion should lead to make an early diagnosis and choose an appropriate empirical treatment to improve the outcome in this population.

Challenges Perceived by Health Care Providers for Implementation of Contact Screening and Isoniazid Chemoprophylaxis in Karnataka, India

Background: In India, challenges in pediatric TB contact screening and chemoprophylaxis initiation are still underexplored. Elucidating these challenges will help in better implementation of the programme at the grass-roots level thereby helping in early detection of pediatric cases and timely initiation of preventive therapy. This study aimed at exploring the challenges faced by the health care provider in contact screening and chemoprophylaxis initiation implementation of the pediatric household contacts. Methods: A qualitative study was conducted in the districts of Bengaluru and Udupi and in-depth interviews of key participants were adopted to explore the challenges. Qualitative data analysis was done after developing transcripts by generating themes and codes. Results: The key challenges were identified as stigma towards the disease, migrant patients with changing address, difficulty in sample collection, anxiety among parents due to long duration of the prophylactic treatment and adherence to IPT is not well documented, inadequate transportation from rural areas, and the ongoing COVID-19 pandemic. Conclusions: It is important for the National TB programme to address these challenges efficiently and effectively. Innovative solutions, feasible engagements, and massive efforts are to be taken by the programme to improve contact screening and isoniazid chemoprophylaxis implementation.